1. Field of the Invention
The present invention relates to a method for starting up a file sharing system and a file sharing device.
2. Description of the Related-Art
In order to share data between a plurality of computers that are distributed across a network, a file sharing device is employed. As an initial-type of file sharing device, a file server that mounts a file sharing protocol such as a CIFS (Common Internet File System) or NFS (Network File System) on a general-purpose OS (Operating System) is known, for example. As an improved file sharing device, NAS (Network Attached Storage), which supports a plurality of file sharing protocols (CIFS, NFS, DAFS (Direct Access File System) or the like) and employs a dedicated OS which is specialized for file sharing services, is known.
In addition to NAS, SAN (Storage Area Network) storage is also known. SAN storage involves inputting and outputting data in block units to and from logical volumes that are set on a physical storage device such as a disk drive. Further, a file sharing system that involves co-operation between a NAS device and SAN storage is also known (Japanese Patent Application Laid Open No. 2005-267530).
The prior art that appears in Japanese Patent Application Laid Open No. 2005-267530 stores information that is required for the setting of the NAS system in a RAID storage area as block data. As a result, the prior art prohibits file access to the setting information and prevents the deletion of information that is required to set the NAS system as a result of an erroneous operation by the user.
In the prior art, as is presented in paragraph number [0024], a NAS disk array control section and disk enclosure are connected via an internal disk interface. In other words, because the NAS device and SAN storage are connected via an internal bus, the NAS device is able to access the disk drive relatively easily.
On the other hand, in cases where a NAS device and SAN storage are connected by using an external communication path for which authentication is required at the time of access as in the case of a file channel connection, for example, the NAS device is required to access the SAN storage by using information such as a preset WWN (World Wide Name) or LUN (Logical Unit Number). In cases where an access request that designates a predetermined LUN that is preset is issued by a device with a predetermined WWN that was preset, the SAN storage permits access.
Therefore, in cases where a NAS device is exchanged, the post-exchange NAS device is required to take over predetermined information such as a WWN or LUN or the like that has been set for the pre-exchange NAS device. This is because, in cases where predetermined information is not taken over, the post-exchange NAS device is unable to access the SAN storage.
In a normal case, the operating system (NAS-OS) whereby the NAS device provides file sharing services has a large capacity and is therefore stored in the SAN storage. The NAS device starts up the NAS system by reading the operating system from the SAN storage and executing same. Hence, because the operating system cannot be read in cases where the post-exchange NAS device is unable to access the SAN storage, the post-exchange NAS device cannot function as a NAS device.